I've actually been getting something like this, on and off, for around four years. Nothing weird about it, really - it's clearly related to wrong numbers. But the first instance was extremely off-putting as it occurred at around 03.00 and the caller has a very croaky, strained and gravelly voice, very much like those alleged 'ghost' voices you sometimes hear on documentaries (think Enfield poltergeist, but a little higher in pitch). I didn't wake in time to take the call, but did immediately check the voice message.
Once I'd got my head sorted I realised that the words were English with some odd usage and the occasional unknown thrown in for measure - and although the voice was too distorted to pin down the accent with any accuracy I surmised that the speaker was Caribbean, West African, or at an outside possibility Indian. (It was an obvious call, but quite a while before it struck me that if I actually entered the unsolicited number on my phone memory it would indicate any related WhatsApp account, and possibly a profile picture - which it did: my West African guess was probably closest the mark.)
The first call was quite stressful, as, aside from initially thinking that I'd been rung up from beyond the veil, I thought at first that the lady was in distress and asking a relation she had intended to call for help: I could pick out the croaky words 'Auntie' and 'help', between rattle-lunged intakes of breath, but, at first, not much else. However, a more thorough listening to indicated it was more likely someone calling a relative that they had not spoken to for a while.
I've had quite a few calls from the lady. I tried engaging once or twice, but, on top of everything else, she is clearly quite deaf. I don't answer now, but she always takes the time to leave a message. I've sent her text messages indicating that I think she possibly has the wrong number, but to no avail. I even got quite worried about her when I stopped getting calls for around twelve months from mid 2019, but received another around four weeks ago (which, I'll admit, was quite a relief - I've become quite attached to the poltergeist voiced auld biddy and thought the virus might have finished her off; lord knows, she sounds like someone who is on an at risk spectrum).
Probably sounds quite anodyne, but, to illustrate the particular power of this lady's voice I should say that at work the next day, while briefing a load of hairy arsed ex squaddies, ex-criminals, ex-ne'er do wells etc on their day ahead, I played the message. Initial nonchalance soon turned to universal consternation: Whooooah! Jeez mon - that sounds like the fuckin undead! I'd nae sleep a wink after that, pal!